Catalysts provide a vital mechanism for facilitating modern industrial-scale chemical production. This is particularly true in petrochemical processing and organics production. The changing demand for specific hydrocarbon products as well as the changing oil feedstock due to shale oil production in competition with traditional crude oil. Catalytic n-butane dehydrogenation is very important for the production of butenes (for example, 1-butene and cis/trans 2-butene) and 1,3-butadiene. In particular, the latter product is important as a precursor for fine-chemical synthesis and both are important for polymer production.
Ideally, catalysts facilitate chemical transformations with a selectivity for desired reactions (and end products) and a practical stability or lifetime before the catalyst is fouled or deactivated. For n-butane dehydrogenation, platinum and platinum group materials have long been used as catalysts. However, energy-intensive nature of the dehydrogenation reaction (typically requiring harsh conditions) has been shown detrimental to the long-term stability and overall efficiency of these platinum catalysts. While high-surface-area substrates, such as silica and alumina, have been utilized as supports for platinum catalysts, such catalysts deactivate as a result of active-site sintering. In particular, silica supports have been considered as poor performers due to the more facile catalyst sintering. For example, U.S. Pat. No. 4,041,099 highlights problems with silica as a support and stresses the use of a silica-free process. Alumina also exhibits undesirable characteristics such as a Lewis acid behavior resulting in cracking into lower value hydrocarbon fragments (C1, C2, and C3).
There is a need for a platinum group catalyst that utilizes high-surface area substrates while maintaining catalyst activity, selectivity and stability.